1. Field of the Invention
The present invention is directed to exercise apparatuses and, more specifically, to exercise apparatuses in which a user's feet move in generally elliptical paths of motion as the apparatus is pedaled by the user.
2. Description of Related Art
Elliptical exercise devices are devices that allow the user to stand on pedals and to drive the pedals in a manner similar to driving the pedals of a stationary bicycle or stair climbing machine. However, unlike stationary bicycles and stair climbing machines, the pedals of an elliptical exercise device traverse a generally elliptical path as the user pedals them, rather than a circular path. The elliptical path of the foot pedals in such an exercise machine simulates a user's stride in walking or running. A resistance system is typically coupled to the pedals to provide the user with resistance as he or she moves the pedals, so as to increase the intensity of the user's workout. The amount of resistance provided by the resistance system is generally controllable by the user.
Elliptical exercise devices have increased in popularity in recent years and many varieties are now commercially available. Representative examples of these devices are described in, for example, U.S. Pat. Nos. 4,786,050; 5,242,343; 5,279,529; 5,352,169; 5,518,473; 5,540,637; 5,549,526; 5,562,574; and 6,063,008.
In a typical elliptical exerciser, the pedals are mounted on elongate members. One end of each elongate member rotates about a crank connected to the resistance system; the other end of the elongate member is free to translate and pivot and is movable along either a reciprocating path or a closed path. For example, in the exerciser disclosed in commonly-assigned U.S. Pat. No. 6,063,008, the ends of the elongate members are supported by bearings.
Because the elongate members are rigid and are free to translate and rotate on one end, some portions of the pedal movements may be jarring for the user. It is advantageous if jarring movement of the pedals can be reduced or eliminated, in order to increase the user's comfort and reduce the likelihood of injury caused by jarring movement of the pedals.
Resilient elements such as springs are sometimes used in elliptical exercisers, although configurations that include springs do not generally reduce jarring movement in the exerciser. For example, U.S. Pat. No. 5,857,941 to Maresh discloses an elliptical exerciser in which the resistance system is coupled to the elongate members by means of a rack and pinion system. Compression springs are used to keep the rack elements in engagement with the pinion elements.
U.S. Patent Application Publication No. 2003/0045401 A1 of Watterson et al. (corresponding to U.S. application Ser. No. 09/943,741) discloses one potential solution to the problem of jarring pedal movement. In the Watterson et al. publication, the elongate members on which the pedals are mounted are leaf springs, which adds resiliency to the movement of the pedals, thereby damping the movements of the pedals. Making the elongate members leaf springs may be relatively costly. Other arrangements are disclosed in U.S. Patent Application Publication No. 2004/0157706.